The invention relates to a sponge rubber mop and more particularly is concerned with a retainer for removably retaining the sponge rubber member.
In utilizing a sponge rubber mop the sponge member must securely be retained within the mop head so the sponge member will be held in the mop head against the friction forces exerted against it when it is in use and moved across a surface. At the same time, the sponge member must be capable of being removed when the exposed surface of the sponge member is dirty or worn out. Preferably, the sponge member may be reversed in the mop head so that at least two separate surfaces may be utilized in the mopping operation before the member is cleaned or disposed of.
The problem presented by a removable sponge mop member, is that it is difficult to retain it securely enough so that it will not roll out when it is being used, and yet allow it easily to be removed for replacement or rotating of the exposed mopping surface. In applying wax, for example, the wax may dry and become sticky, seize the engaged surface and pull the mop member out.
One sponge mop which has a sponge member which may be rotated to utilize all four of the sponge member faces is described in U.S. Pat. No. 3,012,265. In this mop the sponge member has lengthwise grooves which are pinched or resiliently squeezed by the rolled edges of the flanges of the retainer. If the friction force becomes excessive during use, the pinching force exerted by the retainer may not be sufficient, and the sponge member may roll out of the retainer.
A sponge retainer having inwardly opposed flanges is shown and described in U.S. Pat. No. 3,096,534. The inwardly extending flanges are of a single thickness and are engaged in channels or slits in the sponge member. This sponge retainer, however, is specifically directed to a vertical pressing operation and not to a side to side engagement causing friction on the exposed surface of the sponge member. If this sponge retainer were moved from side to side the large flat surface of the sponge member in relation to the small slits in the thin edge would cause the sponge member to roll out of the retainer under a small frictional force.